Self-Tuned Critical Networks

脊椎动物神经系统由神经元组成，这些神经元通过称为突触的连接相互作用。突触连接强度的变化，由于神经元的活动模式，被认为是大脑可塑性的基础。此外，人们普遍认为，突触连接强度的微妙平衡对神经系统功能至关重要。畅通无阻的连接会导致大脑停止运作，在癫痫样的反馈振荡的嘈杂声中；如果压抑占主导地位，刺激将无法从冷漠、扁平的大脑中引发反应。在这两种无用的行为模式之间的微妙界面上，存在着一种制度，即一组神经元处于振荡的边缘，并可能根据外部影响迅速开始或停止反应。这个项目将发展一种自我平衡理论，在该理论中，局部活动依赖于平衡突触反应的规则导致许多神经元组处于这种动态不稳定的边缘。该理论将发展自我平衡与微观结构之间的相互作用，其中局部神经元微电路被串连成整体状态，以及与宏观结构的相互作用，其中不同的自我平衡区域进行交流和相互作用。这一项目产生的新理论将有助于理解大脑中的全球活动模式，如脑电(EEG)或皮层脑电(ECoG)。这项拟议的研究将直接为高中生、本科生和研究生以及博士后研究人员的教育和推广计划做出贡献。这些活动将通过洛克菲勒大学正在进行的项目进行协调。促进少数族裔本科生和研究生参与研究环境将是该计划的优先事项。该项目的成果将被纳入为生物学学生开设的网络理论和高级建模的新研究生课程中。

The vertebrate nervous system consists of neurons that interact with each other through connections, called synapses. Changes in the strengths of the synaptic connections, due to the activity patterns of the neurons, are thought to underlie the plasticity of the brain. Furthermore, it is widely recognized that a delicate balancing of synaptic connection strength is essential to nervous system function. Unhindered connections would cause the brain to cease to operate, in a cacophony of epileptic-like feedback oscillations; if suppression dominated, stimuli would be unable to elicit a response from an apathetic, flatline brain. At the delicate interface between these two useless modes of behavior lies a regime in which groups of neurons are on the verge of oscillation, and may rapidly start or stop responding according to external influences.This project will develop a theory of self-poising, in which local activity-dependent rules for balancing synaptic response result in many groups of neurons poised at the edge of this dynamical instability. The theory will develop the interaction between self-poising and microstructure, in which local neuronal microcircuits are threaded together into global states, and the interaction with macrostructure, in which different self-poised areas communicate and interact. New theory resulting from this project will aid understanding of global activity patterns in the brain, such as Electroencephalography (EEG) or Electrocorticography (ECoG). The proposed research will contribute directly to education and outreach programs for high school students, undergraduate and graduate students, and postdoctoral researchers. These activities will be coordinated through ongoing programs at Rockefeller University. Promoting the involvement of minority undergraduate and graduate students in research environments will be a priority of this program. Results from the project will be incorporated into novel graduate courses on network theory and advanced modeling for biology students.